Tension bolted frame construction



April 9, 1957 N. H. FRANKS 2,788,096

I TENSION BOLTED FRAME CONSTRUCTION Filed NOV. 50, 1953 INVENTOR.

ATTORNEYS.

2,788,096 Y T ENSIUN BULTED FRAME CONSTRUCTION Norvin H. Franks, Chicago, 11!. I

Application November 30, 1953, Serial No. 395,172 Claims. (Cl. 189-36) This invention relates to tension bolted frame constructions and more particularly to a frame construction which can be shipped or stored in completely disassembled condition and easily assembled into a rigid frame unit at the desired point of use. I

Many types of units for both domestic and commercial use such as shelving, frames of various types for use as table bases or for tool supports or the like and various types of stands are so bulky that it is impractical to store or ship them in assembled condition. In my Patent 2,588,818 there is disclosed and claimed a tension bolted frame construction in which sheet metal legs can be easily and quickly secured to metal or like frames to provide a very rigid assembly. As shown in my said patent the frames themselves are pie-assembled as by connecting.

elongated side members together at the corners. The present invention has for one of its objects the provision of an improvement by which frame elements are rigidly connected to each other at the same time that the frame elements are connected to the legs.

Another object is to provide a construction in which a single tension fastening or set of tension fastenings simultaneously secure the frame elements to each other and to the legs.

The above and other objects and advantages of the invention will be more readily apparent from the following description when read in connection with the accompanying drawing, in which- Figure 1 is :a partial perspective view of an assembled corner of a frame construction embodying the invention;

Figure 2 is a perspective view of a corner fastening piece;

Figure 3 is a horizontal section through; the corner showing the parts in disassembled condition;

Figure 4 is a similar view showing the parts in assem bled condition; and

Figure 5 is a partial section on the line 5-5 of Figure 4.

As shown a frame of rectangular shape may be formed of elongated channel elements connected to each other at a right angle and simultaneously connected to a vertical leg indicated generally at 11. The leg 11 is of the same configuration as that disclosed in my Patent 2,588,818 and includes a pair of fiat end flanges 12 lying at an angle to each other which is slightly less than the angle between the frame members 10. For. example with a rectangular frame the angle between the flanges 12 may be on the order of 87 degrees. A pair of integral flat shoulders 13 extend inwardly at right angles from the inner edges of the flanges 12 and the inner edges of the shoulders are connected by an integral fiat panel 14. Preferably the entire leg is formed of sheet metal rolled or otherwise shaped to the desired configuration and the legs, as will be understood, may be made to any preferred length depending upon the particular use to which the frame is to be put. Preferably additional flanges 15 are turned inward from the edges of flanges 12 between the 1* States PatentO 2 points at which the leg is connected to the frame elements 10 to stiifen the leg and give it a smooth edge.

Each of the elements 10 is formed at. its end with a flat end plate 16 which may be formed by bending the end of the channel web inward over the ends of the flanges as shown. The flat end plates 16 are adapted to be seated against the flat shoulders 13 of the legs by fastening pieces as described hereinafter when the frame is assembled.

The parts are adapted to be held together by fastening pieces 17 at each point where the elements 10 meet each other and the legs. As shown in Figure 2, each of the fastening pieces is formed of fabricated sheet metal to provide end plates 18 which are parallel to each other and which are provided with edges 19 lying at the same angles to each other as the frame elements 10. Preferably the end plates are joined by an intermediate integral strip 21 (Figure 3) and the corners of the end plates project beyond the strip to provide a space for receiving a channel 22. The channel may be welded to the strip 21 as indicated at 23, and the channel and strip are preferably formed with openings 24 through which tension -fastenings such as bolts, may pass.

In order to hold the fastening pieces and the frame elements 10 initially assembled, the frame elements are preferably formed in their flanges with semicircular openings 25 spaced from the ends of the elements and having straight edges lying at an angle to the elements. One of the plates 18 is formed with resilient projections 26 to interfit with the openings 25 when the parts are assembled. As shown, the projections 26 are formed in the lower plate 18 by slitting it along straight lines 27 and pressing the material of the plate downward therefrom to form the projections 26.

When the fastening pieces and frame elements are initially put together the resilient projections 26 will snap into the openings 25 resiliently to hold them assembled so that they can be handled more easily until the fastening bolts are inserted.

When the parts are assembled the edges of the flanges of channel 22 will engage the inner surfaces of the end plates 16 on the elements as seen at the lower part of Figure 3. The elements and fastening pieces which are then yieldingly held together by the resilient projections 26 are placed between the flanges 12 of the legs. At this time, tension fastenings such as bolts 23, are inserted through openings in the center fiat panels 14 of the legs and through the openings 24. Nuts 29 are threaded on the bolts and may be drawn up tight to bring the parts to their fully assembled position as shown in Figure 4.

.As the bolts are drawn up the flanges 12 of the legs will be pressed outward so that they engage the outer 1 with the flanges 12 pressing tightly against the outer.

surfaces of the elements 10 which are also engaged by the edges 19 of the end plates 18 to be securely held. The extension of the plates 18 over the flanges of the channel 22 reinforces and strengthens the channel so that it will not spread in response to the load applied thereto, and so that an extremely rigid structure is provided. It has been found that when the bolts are drawn up tightly the assembly is comparable in strength and rigidity to a welded assembly but can be completely disassembled for storage and shipping in small compact packages. Furthermore, the assembly operation is an extremely simple one which can be performed easily with the use of only a simple wrench.

While one embodiment of the invention has been shown and described in detail, it will be understood that this is illustrative only and. is not to be taken as a definition of the scope of the invention, reference being had for. this purpose to the appended claims.

What is claimed is:

I. In a tension bolted frame construction, a leg formed of sheet metal, said leg comprising flat edge flanges lying at an angle to each other, integral flat shoulders projccting inward at right angles to the flanges at points spaced from the edges of the flanges, and an integral fiat panel joining the inner edges of the shoulders, a pair of elongated frame elements lying at substantially the same angle to each other as the flanges and terminating in straight end plates at right angles to the outer surfaces of the elements to seat against the shoulders respectively with the outer surfaces of the elements against the inner flat surfaces of the flanges, a fastening piece having angularly related straight sides engaging the inner surfaces of the frame elements and an outwardly opening channel at the juncture of the sides to receive the end plates with the edges of the channel fitting respectively into the angles between the inner surfaces of the frame elements and the end plates, and a tension fastening connecting the fiat panel to the fastening piece to draw all of the parts tightly together.

2. In a tension bolted frame construction, a leg formed of sheet metal, said leg comprising flat edge flanges lying at an angle to each other, integral flat shoulders project ing inward at right angles to the flanges at points spaced from the edges of the flanges, and an integral flat panel joining the inner edges of the shoulders, a pair of elongated frame elements lying at substantially the same angle to each other as the flanges and terminating in straight end plates at right angles to the outer surfaces of the elements to seat against the shoulders respectively with. the outer surfaces of the elements against the inner flat surfaces of the flanges, a fastening piece including an outwardly opening channel to receive the end plates with the edges of the channel fitting respectively into the angles between the inner surfaces of the frame elements and the end plates and top and bottom stiffening plates secured to the ends of the channel and having angularly related straight sides engaging the inner surfaces of the frame elements, and a tension fastening connecting the flat panel of the leg to the fastening piece to draw all of the parts tightly together.

3. in a tension bolted frame construction, a leg formed of sheet metal with flat edge flanges lying at an angle to each other, integral flat shoulders projecting inward at right angles from the flanges, and an integral flat panel joining the inner edges of the shoulders, a pair of elongated frame elements channel shaped in section with the channels opening inward and lying at substantially the same angle to each other as the flanges, inwardly turned fiat end flanges on the webs of the elements normal to angularly related straight sides to engage the inner surfaces of the Webs of the frame elements, and a tension fastening connecting the flat panel of the leg to the fastening piece to draw all of the parts together, and resiliently interengaging parts on one of the plates and one of the edge flanges of the elements to hold the parts assembled prior to mounting of the tension fastening.

4. A bolted frame construction comprising a leg formed of sheet metal with flat edge flanges lying at an angle to each other, integral shoulders projecting inward at right angles to the flanges at points spaced from the edges of the flanges, and an integral panel joining the inner edges of the shoulders, 21 pair of elongated frame elements lying at substantially the same angle to each other as the flanges and terminating in straight end plates at right angles to the outer surfaces of the elements and seating against the shoulders respectively with the outer surfaces of the elements against the inner flat surfaces of the flanges, a fastening piece of generally triangular shape having straight sides at the same angle to each other as the frame elements and engaging the inner sun faces of the frame elements, the fastening piece being notched at the apex of the triangular shape to provide a pair of outwardly facing edges near the juncture of the sides fitting respectively into the angles between the inner surfaces of the frame elements and the end plates, and fastening means extending through the leg and the fastening piece and drawing them together with the frame elements between them.

5. A bolted frame construction comprising a leg formed of sheet metal with flat edge flanges lying at an angle to each other, integral shoulders projecting inward at right angles to the flanges at points spaced from the edges of theflanges, and an integral panel joining the inner edges of the shoulders, a pair of elongated channel section frame elements mounted with their channel sections opening inwardly and with their webs tying at substantially the same angle to each other as the flanges of the leg, straight end plates extending inwardly at right angles to the webs of the frame elements seating against the shoulders respectively with the outer surfaces of the webs fitting against the inner fiat surfaces of the flanges of the leg, :1 fastening piece including top and bottom generally triangular members whose sides are at the same angle to each other as the frame elements and vertical means joining; the top and bottom members said plates being notched at the apex to provide a pair of spaced edges, the fastening piece fitting into the channel shaped frame elements with said sides engaging the inner surfaces of the webs and said edges, fitting into the angles between the inner surfaces of the webs and the end plates respectively, and fastening means extending through the leg and the fastening piece and drawing them together with the frame elements between them.

References Cited in the file of this patent UNITED STATES PATENTS 2,304,481 Shannon Dec. 3, 1942 2,307,126 Green et a1. .ian. 5, 1943 2,330,766 Walstrom Sept. 28, 1943 2,588,818 Pranks. Mar. ll, 1952 OTHER REFERENCES Product Engineering, page 106, May, 1950. 

